The determination of the date of Pascha—known as Easter in English-speaking countries—has been one of the most historically significant and controversial issues in Christian liturgical history. Despite its centrality in Christian faith—as the commemoration of the resurrection of Jesus the Messiah—Christians around the world often celebrate this foundational feast on different days. This article explores the origin of the Paschal date, the divergent calendars and calculations of Eastern Orthodox, Roman Catholic, and Protestant churches, and how these differences emerged and persist to this day. Finally, we reflect on the profound spiritual message of unity found in the Greek text of Ephesians 4:3.
Jewish Roots and Apostolic Origins
The Christian celebration of Pascha originates in the context of Second Temple Judaism, particularly the Jewish feast of Pesach (Passover), which commemorates Israel’s deliverance from slavery in Egypt. According to the Synoptic Gospels (Matthew, Mark, Luke), the Last Supper was a Passover meal, making the Crucifixion occur during or just after Passover. The Gospel of John, however, portrays the Crucifixion occurring at the time the lambs were being sacrificed—implying a theological link between Christ and the Passover lamb.
The early Church, particularly in the East, celebrated Pascha on the 14th of Nisan, the same day as Jewish Passover. This practice, known as Quartodecimanism (from Latin quartodecimus, meaning “fourteenth”), was widespread in Asia Minor. However, in other parts of the Church, such as Rome and Alexandria, Pascha was celebrated on the Sunday following the 14th of Nisan, emphasizing the resurrection over the day of the death.
The Quartodeciman Controversy and Council of Nicaea
The disagreement came to a head in the 2nd century when Victor I (bishop of Rome, c. 189–199) attempted to excommunicate Quartodeciman communities. Although rebuked by Irenaeus of Lyons, this action highlighted deepening divisions.
In 325 A.D., the First Council of Nicaea, convened by Emperor Constantine, addressed the Paschal controversy. The Council decided that Pascha should be celebrated on the Sunday following the first full moon after the vernal equinox, and that it should not coincide with the Jewish Passover. Although the Council did not formally specify a unified calculation method, the Alexandrian method—which used a sophisticated 19-year lunar cycle—eventually became the standard for calculating the date in the West.
Calendrical Divergences: Julian vs. Gregorian
The Council’s decision assumed the use of the Julian calendar, introduced by Julius Caesar in 45 B.C. Over time, however, the Julian calendar drifted out of sync with the actual solar year by about 11 minutes per year. By the 16th century, this drift resulted in a discrepancy of roughly 10 days.
To correct this, Pope Gregory XIII instituted the Gregorian calendar reform in 1582. The Gregorian calendar omitted 10 days and introduced a refined leap year rule to more accurately match the solar year. While Catholic countries quickly adopted the reform, Orthodox churches—particularly in Eastern Europe and the Middle East—retained the Julian calendar for liturgical purposes.
Because the date of Pascha is determined by the vernal equinox and the full moon, and because the two calendars reckon both differently, Catholics/Protestants and Orthodox Christians often celebrate Pascha on different dates.
Paschal Computus: Astronomical vs. Ecclesiastical Methods
Western Christianity (Catholics and most Protestants) uses the Gregorian calendar and a mathematical formula called the computus, which approximates the date of the ecclesiastical full moon. This computus uses a fixed ecclesiastical equinox set on March 21 and a calculated ecclesiastical full moon, which does not always align with the actual astronomical full moon. These approximations, although consistent with church tradition, sometimes diverge from astronomical observations.
Orthodox churches use the Julian calendar, and thus their calculations of the equinox and full moon are about 13 days behind the Gregorian reckoning. Additionally, the Orthodox Church insists that Pascha must always occur after Jewish Passover, to preserve the biblical sequence of events.
These different calculation methods often result in different dates for Pascha—sometimes by as much as five weeks.
Why Do Protestants Usually Follow the Catholic Date?
After the Reformation, most Protestant churches, including Anglicans and Lutherans, retained the traditional Western liturgical calendar. As a result, they continue to observe Pascha based on the Gregorian computus, alongside Roman Catholics. Some Protestant groups, particularly in Eastern Europe, follow the Orthodox calendar due to geographical and historical alignment.
Modern Ecumenical Efforts at Unity
The World Council of Churches and various ecumenical initiatives have long recognized the scandal of disunity in the celebration of Pascha. In 1997, a proposal was made to base the Paschal date on astronomical calculations (the actual equinox and full moon, as observed from Jerusalem), but this has not been implemented universally.
In recent years, popes and patriarchs have expressed openness to finding a common Paschal date. For example, Pope Francis and Patriarch Bartholomew I have discussed the possibility of aligning the celebration. Still, resistance remains, particularly from churches that see the Julian calendar as a sacred inheritance of the undivided Church.
When Pascha Coincides: 2025 as a Moment of Unity
In 2025, something extraordinary will occur: Orthodox, Catholic, and Protestant Christians will celebrate Pascha on the same day—April 20, 2025. This rare alignment is a result of overlapping full moon calculations and equinox dates.
Historically, such coincidences occurred in:
– 2010
– 2011
– 2014
– 2017
– 2025 (today)
– 2034 (future)
This synchronicity offers an opportunity for deeper ecumenical reflection, joint worship, and theological dialogue. It reminds us that while our calendars may differ, our Risen Lord is one.
σπουδάζοντες τηρεῖν: A Call to the Unity of the Spirit
Let us close with a word from the Apostle Paul, written to the early believers in Asia Minor—many of whom once debated the date of Pascha themselves:
σπουδάζοντες τηρεῖν τὴν ἑνότητα τοῦ Πνεύματος ἐν τῷ συνδέσμῳ τῆς εἰρήνης
“Eager to maintain the unity of the Spirit in the bond of peace.” — Ephesians 4:3
This year, as Christians around the world celebrate the resurrection of the Messiah together, may we heed Paul’s exhortation: to strive with eagerness (σπουδή) for spiritual unity—not only in doctrine and tradition, but in the lived experience of love, forgiveness, and shared resurrection hope.
Χριστὸς ἀνέστη! Ἀληθῶς ἀνέστη!
Christ is risen! Truly, He is risen!
